What is another name for the cardiac pacemaker?

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Multiple Choice

What is another name for the cardiac pacemaker?

The heart’s natural pacemaker is the sinoatrial node. Located in the right atrium near where the superior vena cava enters, its cells have the highest intrinsic rate of spontaneous depolarization. This means it fires action potentials first, setting the pace for the heart's rhythm (the sinus rhythm) and initiating the heartbeat. The impulse then travels to the atrioventricular node, causing a brief delay that lets the atria finish contracting before the ventricles are stimulated. Other components of the conduction system—like the atrioventricular node, Purkinje fibers, and the Bundle of His—can pace the heart if the SA node fails, but they do so at slower, less reliable rhythms, making them secondary pacemakers.

The heart’s natural pacemaker is the sinoatrial node. Located in the right atrium near where the superior vena cava enters, its cells have the highest intrinsic rate of spontaneous depolarization. This means it fires action potentials first, setting the pace for the heart's rhythm (the sinus rhythm) and initiating the heartbeat. The impulse then travels to the atrioventricular node, causing a brief delay that lets the atria finish contracting before the ventricles are stimulated. Other components of the conduction system—like the atrioventricular node, Purkinje fibers, and the Bundle of His—can pace the heart if the SA node fails, but they do so at slower, less reliable rhythms, making them secondary pacemakers.

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